The Rakelli are a serpentoid species who live, and originate, within space that is currently claimed by the Klingon Empire. The Rakelli are hostile towards the Klingons as they claim that Klingon space was part of a once mighty Rakelli Empire which the Klingons conquered in the past. Ever since the fall that, which took place in the late 23rd century, the Rakelli have sought vengeance against the Klingon Empire by raiding convoys and starships.
After the year 2385, the Rakelli became a part of the Federation protectorate and have been given a new homeworld which they use to rebuild their race. This has made them allies of the Federation/Klingon alliance.